I am going to guess that she will end up having a bigger role in Dany's inner circle.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*Poor Tyrion*

His trial probably isn't going to be fair and they will use everything he has said about Joffrey against him.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*Sansa*

I hope she has enough sense when to ask Baelish questions and when she shouldn't and that she shouldn't ever trust him. I think Sansa is going to be in trouble for being a part of the conspiracy against Joffrey although she didn't know she was being a part of it.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*Olenna*

I don't think she will be caught. I think she will die first of natural causes before the truth ever gets out.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*Margaery*

I think she will end up marrying Tommen, however I think she eventually will be offed by Cersei.

I don't see Brienne and Pod. I mean I can see it on screen, it would make sense given they're both lovely people and they are trapped together. But that makes too much sense! I'm assuming she is destined to be miserable for a while yet and never discover his amazing bedroom skills.

I think maybe Cersei will do something major to get rid of Margaery and Loras despite it being in her family's interests to maintain good relations. Again Margaery seems too good at playing people. On this show that seems to lead to something bad happening...

Brienne does have a pattern of falling in love with men. She first respects them for some act (could be fighting skill or saving some one) and then that respect changes to love. This happened with Renly, Jaime and perhaps Pod. If he saves her life in a fighting manner showing off his skills and good qualities that might warm her up.

I think you are right about Cersei. Tywin's comment about Cersei thinking she's smarter than she is actually is dead on and her emotions can get the better of her some times. I can see Cersei playing nice with Margaery and Loras at first. I don't imagine Loras and her will ever have bedroom relations. Potentially the Loras Cersei wedding night sequence if done right could be quite funny. Later as time goes on Cersei's emotions could get the better of her and she could do something to Loras and Margaery. It would be really good TV if Margeary ends up getting the better of Cersei and they become perfect foils.